Examination of ADAR-RNA and ADAR-ADAR interactions

RNA within a cell is subject to multiple processing events prior to undergoing translation, including RNA editing through the chemical modification of RNA bases. An example of this is adenosine deamination to produce inosine, a reaction carried out in mammalian cells by the adenosine deaminases that act on RNA (ADARs). The experiments presented in this thesis examine both ADAR - RNA and ADAR - ADAR interactions using in vitro and in vivo techniques. Through the use of footprinting we were able to identify regions on a model substrate which were protected upon binding of an ADAR2 homodimer. Utilizing fluorescence microscopy, we were able to determine that ADAR1 and ADAR2 form both homodimers and heterodimers within the nucleoli of HeLa cells. This thesis also reports our endeavors at characterizing novel extra-nucleolar regions to which ADAR1 was discovered to localize. The results within suggest methods by which adenosine deamination is regulated within the cell.